NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar NARI Fluorescence-Doped Particles for Simultaneous Temperature and Velocity Imaging Principle Investigators: P. M. Danehy, P. Tiemsin, C. Wohl, (NASA Langley Research Center) Additional Team Members: T. Lowe and R. Simpson (Va Tech)
Outline NARI • Current state of the art • Technical approach • The innovation: key points • Impact of the innovation if it is eventually implemented • Results of the seedling Phase I effort to date • Distribution/Dissemination – getting the word out • Next steps June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 2
Current state of the art NARI • Most common measurements in wind tunnels are lift, drag, force and moment – Also: surface pressure, surface heat transfer • Off body, most common techniques: – Schlieren, non-quantitative flow vis – Laser Doppler velocimetry (LDV), u, v at a point – Particle Image Velocimetry (PIV), u, v in a plane • Measurements not readily available: – In stream temperature, pressure, concentration Need: Easy to use, turn key, safe June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 3
Why Use Particles? NARI • Other ways of measuring flow temperature (without seeding particles) exist, but have limitations preventing their use: – CARS: complicated, expensive, hard to set up, single point, 10 Hz – Rayleigh/Raman scattering: low signal, complicated to analyze, often single point, 10 Hz – PLIF: must seed flow with (usually) toxic gas, complicated, not very accurate, not sensitive enough, 10 Hz – Thermocouple: intrusive probe, single point, slow time response • Few or no viable methods of measuring flow pressure exist • Seeding dye-doped particles into a flow to measure T , P , and/or stream concentration should allow high s/n images – Easy because uses same or similar lasers, seeding systems, detectors as PIV/LDV prefer imaging, non-toxic seeding – Performing in conjunction with PIV/LDV will measure multi-parameters June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 4
NARI Technical Approach: Measure T Dye-doped Particles If dye has T dependence… Fluorescence Mie Scattering Laser LIF MIE Temperature Temperature (only) Measurement Approach June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 5
NARI Technical Approach: Measure P Dye-doped Particles Dye fluorescence lifetime depends on pressure… Fluorescence Laser LIF P 1 P 2 Time Pressure (only) Measurement Approach using Lifetime Measurement (could also measure intensity of signal referenced to Mie) June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 6
Technical Approach: Combine w’ LDV NARI Measure velocity Dye-doped from frequency of Particles collected light from particle passing through fringes… Fluorescence Mie Scattering Laser DET1 Time Measure velocity from LDV, Pressure or Temperature from fluorescence June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 7
Technical Approach: Imaging Example NARI Combine T, P or concentration measurement with Particle Image Velocimetry (PIV) June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 8
Technical Approach: PSLs NARI Negatively charged Charge neutralization enables monomer liquid polymerization initiation by droplet persulfate radical 2- S 2 O 8 Styrene Mg 2+ Mg 2+ Mg 2+ Mg 2+ Mg 2+ Styrene Mg 2+ Polystyrene Mg 2+ Latex Spheres Mg 2+ (PSLs) Magnesium cations Mg 2+ neutralize negative charge Dye- How do we attach the dye? June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 9
NARI Technical Approach: Dye Doping A B C D Premature Particle- Styrene- Dye- Dye with a Styrene functionality- Mature Particle- June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 10
NARI Technical Approach: Dye Doping A B C D Premature Particle- Styrene- Dye- Dye with a Styrene functionality- Mature Particle- June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 11
Innovation: Key Points NARI • Have identified multiple measurement approaches with different dyes and different laser and detector configurations to measure: – Temperature, Pressure, Concentration – Pointwise (fast) or imaging (10 Hz) are possible – Alone or simultaneous with LDV, PIV • PSLs have been synthesized with an array of dye materials with varying degrees of success – Dye influence on particle size and size distribution was observed and characterized – Different methods of incorporating dyes explored • Temperature measurement in a flow experiment was demonstrated with (VT, POC: Todd Lowe) June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 12
Impact of Innovation if Incorporated NARI • Extend measurement technology beyond force/moment/wall and u, v velocity measurements – Temperature, Pressure, Concentration • Impact on NASA ARMD Programs: – SFW/ERA: Jet noise studies, T, u, v and correlations – Rotary Wing: Pressure disturbances near blade tips – High Speed: Sonic Boom simultaneous P, u, v measurement – Measurements would provide unique data for validating CFD codes in a way not currently possible. • Have identified potential customers within NASA, at other government agencies, academia and industry. June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 13
Phase I Results NARI • Dye materials evaluated λ exc , nm λ em , nm Dye PSL Incorporation notes Potentially Rhodamine B 575 595 Great, no leaching carcinogenic Solvent dependent Fluorescein 548 512 526 Non-carcinogenic emission Non-carcinogenic Kiton Red 620 554 575 Leaching issues Tunable spectral Tetraphenyl Porphyrin 400 655 Inefficient incorporation properties Other materials evaluted including fluorenone, 4-hydroxycoumarin, and Malachite Green. June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 14
Phase I Results: Rh B N + (Et) 2 N O NARI CO 2 H • Rhodamine B: Very strong Signal - But slightly toxic 1.2 • Spectrum shifts in PSLs: In Water In PSLs Excitation and emission 1 properties of Rhodamine dyes 0.8 Intensity, a.u. are strongly dependent on 0.6 matrix properties In Water In PSLs 0.4 Excitation 546 nm 575 nm 0.2 Maximum Emission 585 nm 595 nm 0 Maximum 500 550 600 650 700 Wavelength, nm • Decreases particle size ~10% June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 15
O HO O Phase I Results: FL548 Cl Cl COOH NARI • Fluorescein 548 – Showed good signal and temperature sensitivity in preliminary tests – Shows Complex Emission/Quantum Yield Behavior • Excitation at 532 nm. 50 • Emission intensity 45 Fluorescent Emission Intensity, a.u. Have obtained a 40 diminishes significantly and different type of 35 rapidly as solution Fluorescein dye that 30 evaporated. emits even when dry: 25 will try soon. 20 • No detectable signal after 15 the deposited PSLs were 10 allowed to dry. 5 0 500 550 600 650 700 750 800 Wavelength, nm June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 16
Phase I Results: KR N + (Et) 2 N O - SO 3 NARI - Na + SO 3 • Kiton Red – Less Toxic than Rh B 250 – Lower signal than Rh B – Better for concentration meas. Fluorescent Emission Intensity, a.u. 200 – Dye Leaching out: 150 100 • Once PSLs have settled, 50 there is a clear distinction in color between the PSLs 0 500 600 700 800 (white) and aqueous Wavelength, nm solution (red). June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 17
Phase I Results: Leaching NARI • Leaching Studies Rhodamine B-doped PSLs Kiton Red-doped PSLs Even if Rh B is slightly toxic, if it is encapsulated in a polymer and won’t leach out (in water), might it be acceptable for use? June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 18
NARI Phase I Results: Porphyrin N N NH N Mg +2 N N HN N Porphyrin -Suitable for pressure measurement Fluorescent Emission -So far, low signal intensity 100 Complex Spectroscopic 90 λ max : 655 nm 80 Properties: Emission Intensity, a.u. 70 • Coordination of an ion in the center 60 of the macrocycle impacts: 50 – Fluorescent emission 40 – Quantum yield 30 – Phosphorescent properties 20 – Propensity for PSL incorporation? 10 PSL synthesis uses MgSO 4 resulting in • formation of a Mg-TPP adduct: 0 Chlorophyll-like 350 450 550 650 750 Wavelength, nm June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 19
NARI Phase I Results: Concept Demo I Rh B doped Particles If dye has T dependence… Fluorescence Mie Scattering 532 nm LIF Laser MIE Temperature Va Tech demonstration used first measurement approach described above (Lowe, VT) June 5-7, 2012 NASA Aeronautics Mission Directorate FY11 Seedling Phase I Technical Seminar 20
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